docs: def create_from_request_pdu(pdu):
  
          """ Create instance from request PDU.
          :param pdu: A request PDU.
          :return: Instance of this class.
          """
          _, starting_address, quantity = struct.unpack('>BHH', pdu)
  
          instance = ReadHoldingRegisters()
          instance.starting_address = starting_address
          instance.quantity = quantity
  
          return instance